Study On The Mode Parameter Identification And Suppression Of The Oscillation Of Power System

The object of study is based on power system small signal lower frequencyoscillation, improving the methods for identification of modal parameter of the lowfrequency oscillations. In the modal control concepts, studying on the control methodand strategy of the low-frequency oscillations.Methods for identification of modal parameter of the low frequency oscillation isusually through the band-pass filter and wavelet filters method for signal filtering andcalculation system of characteristic roots. This paper improves the methods of modalparameter identifications. Decomposition filtering of the object are measured from themeasured torsional vibration signal extraction synchronization component group byusing the empirical mode to realize the filtering functions of the original signal.Andsuperimposed into an unified subsynchronous component by the Prony algorithm forthe parameter identification, In order to take more accurate identification result, to getbetter reflect the actuall working conditions,The accuracy of calculation of theresampling is improved by the optimization systems.Through the simulation analysis,higher precision of modal parameters identification methods are improved and to meetthe identifications of the torsional component requirements.Controlling methods of the low frequency oscillations are optimized, achievingdecoupling function between the modes by means of the equivalent modal controls.With the band filter using frequencies divider,the separations of proposed controlingstrategy is made. In the condition of different frequency modes,different controlingmethods are used, designing of the excitation control systems in the higher frequencyband branch; designing of speed controling mode in the low frequency band branches.The designs of control mode is in different frequency bands. The control actuatorresponse speed and damping frequency are corresponding to each other. Each mode ofindependent controling function, then the control effectting to achieve suppression oflower frequency oscillation. Based on the two regional system simulations, to get thecalculation of system eigenvalues.Characteristic root with equivalents mode under thecontrol of the match is easy to get: the accuracy of the approach is high, and verifyingthe feasibility of the controlling method.